if 表是否，则用什么时态？表如果，用什么时态？

Question

最好有例句。

Answer 1

如果：

zero conditional: 100% 会发生的事：
If water reaches 100°, it boils.
如果水达到了100度，就会烧开了
if + present simple(reaches), present simple (boils)

first conditional： 非常非常有可能 95% 会发生的事：
If you study more, you will pass this exam.
如果你更用功点， 你就会通过这个考试
if + present simple (study), will + base form (will + pass)

second conditional: 可能性不算很大 60%
If I had the time, I would study Italian.
如果我有时间的， 我想学意大利语
if + past simple (had), would + base form (would + study)

third conditional: 白日做梦
If I had won the lottery, I would have bought a bigger house.
如果我中了奖， 我就想买一个大点的房子
if + present perfect (had won), would + present perfect (would + have bought)

是否:
要按照时间顺序：
I don't know if my father is here.
present(don't know),if + present (is)
我不知道我爸爸在不在这里

I don't know if my father has been here.
present (don't know), if + past simple/present perfect(was/has been)
我不知道我爸爸有没有在这里过

I don't know if my father will be here
present (don't know), if + future (will + base form)
我不知道我爸爸将来会不会在这里

I didn't know if my father was here
past simple (didn't know), if + past simple (was)
我当初不知道我爸爸在不在这里

I didn't know if my father had been here.
past simple (didn't know), if + past perfect (had been)
我当初不知道我爸爸有没有在这里过

I didn't know if my father would be here.
past simple (didn't know), if + conditional (would + base form)
我当初不知道我爸爸以后会不会在这里