Theory:

Meanings of the difficult words from the lesson "I Want Something in a Cage":
  
S.No
Words
Meanings
1
GhostThe spirit of a dead person sometimes represented as a pale, almost transparent image of that person that some people believe appears to people who are alive
2
DoveA white or grey bird often used as a symbol of peace
3
Strange Unusual and unexpected, or difficult to understand
4
UncannyStrange or mysterious; difficult or impossible to explain
   5Profession Used to describe someone who does a job that people usually do as a hobby
6
CustomerA person who buys goods or a service
7
LingerTo take a long time to leave or disappear
8
Musty Smelling unpleasantly old and slightly wet
9
AbandonLeft in a particular place or condition, usually forever
10
Haunted A place where ghosts often appear
11
Fussy Not easily satisfied, or having very high standards about particular things
12
Appearance The way that someone or something looks
13
Genial Friendly and pleasant
14
Remedy A successful way of curing an illness or dealing with a problem or difficulty
15
CanaryA small, yellow bird that is well known for its singing, sometimes kept as a pet
16
Ailing Experiencing difficulty and problems
17
Ornate Having a lot of decoration
18
Gilded cageSomeone or something was trapped in or living a restricted life or living without any freedom
19
PervadeTo spread through all parts of something
20
Whisper A soft, low noise
21
RustlingMake a soft, muffled crackling sound like that caused by the movement of dry leaves or paper
22
SquealA long, high-pitched cry or noise
23
CheepA shrill squeaky cry made by a bird, typically a young one
24
SqueakA short, high-pitched sound or cry
25
Scamper Especially of a small animal or child run with quick light steps, especially through fear or excitement
26
Frantic Wild or distraught with fear, anxiety, or other emotion
27
FrightenFeeling fear or worry
28
BewildConfused and uncertain
29
Flicker A feeling or expression of an emotion or quality that does not last very long
30
Briskly Quick, energetic, and active
31
Rub his hands To be in keen or greedy anticipation of something
32
PulseTo move or beat with a strong, regular rhythm
33
TwitterOf a bird to make a series of short, high sounds
34
Routine A usual or fixed way of doing things
35
Proprietor A person who owns and usually manages a business
36
Custom A way of behaving or a belief that has been established for a long time
37
Perch To sit on or near the edge of something
38
Digest To read or hear new information and take the necessary time to understand it
39
SmirkA smile that expresses satisfaction or pleasure about having done something or knowing something that is not known by someone else
40
FrownTo bring your eyebrows together so that there are lines on your face above your eyes, often while turning the corners of your mouth downwards, showing that you are annoyed, worried, sad, or thinking hard
41
Purse his lipsTo bring your lips tightly together so that they form a rounded shape, usually as an expression of disapproval
42
Out of thin airSomeone or something appears in a sudden and unexpected way
43
FrostCover something with or as if with small ice crystals; freeze
44
Glance Take a brief or hurried look
45
HeadlineA heading at the top of an article or page in a newspaper or magazine
46
Chirping Typically of a small bird or an insect utter a short, sharp, high-pitched sound
47
Mewing High-pitched cries characteristic of a cat or some kinds of bird
48
StoolA seat without a back or arms, typically resting on three or four legs or on a single pedestal
49
Instant Happening or coming immediately
50
UnreasonablyIn a way that is not fair or acceptable
51
NodSignify or express greeting, assent, or understanding by nodding
52
Ill-fitting Of a garment of the wrong size or shape for the person wearing it
53
Shuttling glance Constantly looking to and fro
54
Cold spellA period of cold weather
55
ConfuseOf a person unable to think clearly; bewildered
56
SnapSomething said in an angry way
57
HastenTo make something happen sooner or more quickly
58
MagnanimouslyIn a way that is kind and generous, especially towards an enemy or someone you have defeated
59
Suspended Supported by attachment from above; hanging
60
Prompt Done without delay; immediate
61
CrestfallenSad and disappointed
62
Reduction A thing that is made smaller or less in size or amount
63
ProfitMoney that is earned in trade or business after paying the costs of producing and selling goods and services
64
TiptoeWalk quietly and carefully with one's heels raised and one's weight on the balls of the feet
65
UnhookUnfasten or detach something that is held or caught by a hook
66
CustomerA person or organization that buys goods or services from a store or business
67
Cocked his head Moved his head quickly
68
ChitteringMake a twittering or chattering sound
69
Scurry Of a person or small animal move hurriedly with short quick steps
70
BlurtedSay something suddenly and without careful consideration
71
CrazyAnnoyed or angry
72
InsaneExtremely unreasonable, or mentally ill
73
LabourWork, especially hard physical work
74
Merchant A person whose job is to buy and sell products in large amounts, especially by trading with other countries
75
Humour To do what someone wants so that they do not become annoyed or upset
76
MopTo use a cloth to remove sweat from the face 
77
Sweat The clear, salty liquid that you pass through your skin 
78
Pucker  To tighten skin or cloth until small folds appear or of skin or cloth to form small folds
79
Perplex To confuse and worry someone slightly by being difficult to understand or solve