agree with captain match and also "先" means first, not "you have to"
It might be better that turn left is translated as 左轉
This or 往右拐
Also, 先 is first, so the English is misleading
I am beginning to doubt if I know Chinese. Apparently 20 years of using the language can't fool a computer.
Yes, I'm not sure if the Chinese language is suited to Duolingo.
Combining what the users first posted, we have the following possible sentences (including my tweaks):
The Chinese doesn't say "have to" in any way