Syntax: This is a compound sentence with two independent clauses joined by 'But.' The first clause uses the present perfect continuous tense ('I've been waiting') to show an action that started in the past and continues to the present. The second clause uses the past progressive ('could go wrong') in a negative construction to express a past belief about a future possibility.
Morphology: 'Waiting' is the present participle of 'wait.' 'Thinking' is the present participle of 'think,' used here to form the past continuous aspect ('was thinking' is implied). 'Could' is the past tense of 'can,' used here to express past ability or possibility.

Syntax: This is a complex sentence. The main clause is 'She has a built in ability.' The infinitive phrase 'To take everything she sees' functions as an adjective, modifying 'ability.' The relative clause 'she sees' modifies 'everything.' The final line is a separate sentence using the present continuous tense ('I'm falling') to indicate an ongoing action in the present.
Morphology: 'Built-in' is a compound adjective. 'Ability' is a noun derived from the adjective 'able.' 'Sees' is the third person singular present tense of 'see.' 'Falling' is the present participle of 'fall.'

Syntax: The structure 'She seems to have...' uses the verb 'seems' (linking verb) followed by an infinitive ('to have') to express appearance or perception. 'Reaches in and grabs' uses the simple present tense for a habitual or characteristic action. 'It takes control' uses the simple present tense to describe what the 'touch' characteristically does.
Morphology: 'Seems' is the third person singular present tense of 'seem.' 'Reaches' and 'grabs' are third person singular present tense verbs. 'Tears' is the third person singular present tense of 'tear' (meaning to rip apart).

Syntax: This is a compound-complex sentence. The first independent clause is 'I don't really know her,' and the second is 'I only know her name,' joined by a comma. The conjunction 'But' introduces a contrasting independent clause with a subordinate clause ('You're never quite the same') that states the result of her action ('crawls under your skin').
Morphology: 'Don't' is the contraction of 'do not.' 'Know' is the base form of the verb used with 'do not.' 'Crawls' is the third person singular present tense of 'crawl.' 'You're' is the contraction of 'you are.' 'Same' is an adjective.

Syntax: The line uses the simple present tense ('don't like,' 'it's') to describe her general characteristics. 'Though' introduces a concessive clause, admitting a fact ('she will mess up your life') that contrasts with the main clause ('You'll want her just the same'). 'Will' is used for future certainty.
Morphology: 'Losing' is the gerund form of 'lose,' functioning as the object of the verb 'like.' 'Mess up' is a phrasal verb. 'You'll' is the contraction of 'you will.' 'Same' is an adverb in this context, modifying the verb 'want.'