Confusing English Words – if / whether

بسیاری از کلمات وجود دارند که معنی یکسانی دارند، اما در واقع تعاریف و کاربردهای مختلفی دارند.
شما می خواهید درست صحبت کنید و از به کار بردن کلمات نادرست خودداری کنید، اما در مورد معنی دقیق و کاربرد هر کلمه کاملا مطمئن نیستید.
بعضی از زبان آموزان حتی به دلیل تردیدهایشان از به کار بردن کلمات خودداری می کنند!
هدف ما در این سری از پست ها روشن کردن رایج ترین کلمات گیج کننده در انگلیسی است.

if / whether

You can use whether or if interchangeably in indirect questions. “If” is more informal and more common in spoken English. “Whether” is more formal and should be used in formal writing

?Do you know if/whether he has a girlfriend
?Could you tell me if/whether the supermarket is open on Sundays
.I was wondering if/whether you’d like to join me for lunch

:There are some cases where we MUST use whether

Before infinitives (to + verb)

.I don’t know whether to tell him or not. = I don’t know if I should tell him or not
.She’s trying to decide whether to travel or continue her studies. = She’s trying to decide if she should travel or continue her studies

After prepositions (about, on, over, etc.)

.We’re thinking about whether we’d rather go out or stay in tonight
.It depends on whether it’ll be rainy or sunny

:Always use if to introduce a condition, in a conditional sentence

My boss gets mad if I’m late for work. (Condition = I’m late for work. Result = my boss gets mad)
If you drive me to the airport, I’ll give you $15 for gas. (Condition = you drive me to the airport. Result = I’ll give you $15)
I’d surf every day if I lived near the beach. (Condition = living near the beach. Result = surfing every day)
If we’d left home earlier, we wouldn’t have missed our flight. (Condition = leaving home earlier. Result = not missing the flight)