These are all so-called if-clauses. The best way to succeed with such an exercise is to study the four main forms of if-clauses in English (zero, first, second, and third conditional) as well as some mixed forms.
ZERO Conditional (always true)
"When it rains, I take an umbrella."
WHEN + present simple //COMMA// present simple
FIRST Conditional (likely future)
"If it rains tomorrow, I will take an umbrella."
IF + present simple //COMMA// will + infinitive (or going to + infinitive)
SECOND Conditional (hypothetical future)
"If it rained tomorrow, I would take an umbrella."
IF + past tense (or 'were' for the verb 'to be') //COMMA// would (could, might) + infinitive
THIRD Conditional (imagining an alternative scenario in the past, even thought the past cannot be changed)
"If it had rained yesterday, I would have taken an umbrella."
IF + past perfect //COMMA// would (could, might) + have + past participle
As for your sentences:
- had not missed (third conditional => imagining an alternative scenario in the past)
- robbed (second conditional => hypothetical future imagining an unlikely situation in the future)
- listens (first conditional => realistic future imagining a likely future)
- would have never met (third conditional => imagining an alternative scenario in the past).
- would be (second conditional => hypothetical future imagining an unlikely situation in the future)
- had not become (second conditional => hypothetical future imagining an unlikely situation in the future)