For example:

If tourists didn’t have questions, I wouldn’t help them.

* “If” is also known as “whether”, but “whether” is used with “or”. 

For example:

I don’t care whether you go to McDonald’s or go to Burger King.

Audio 10

Type 3

*If – clause                       ,                 Main - clause

(simple past)                        (Auxiliaries   could or might)

For example:

If the hotel had many tourists, the receptionist could be very busy.
If the receptionist worked fast, customers might feel comfortable.

Note: You can also use “couldn’t” or “might not”.

For example:

If the receptionist had an old - version PC*, she couldn’t work fast.
If the receptionist had an old – version PC, she might not work fast.

Audio 11

Type 4

*If – clause                ,               Main - clause

(Past verb to be)              (Auxiliary        would or wouldn’t)

For example:

If I were you, I would visit Peru.
If I were you, I wouldn’t be worry about the trip.

Note: We sometimes use “were” instead of “was”, especially in the clause “If I were you”.