1.How long ------- you -------- here?-Till next Friday.A.are;staying B.do;stay C.here;stayed D.had;stayed2.You will not go to the party,will you?-No,--------- I've been invited.A.if B.though C.unless D.because(我选的是C，但答案是B）

1.How long ------- you -------- here?-Till next Friday.A.are;staying B.do;stay C.here;stayed D.had;stayed2.You will not go to the party,will you?-No,--------- I've been invited.A.if B.though C.unless D.because(我选的是C，但答案是B）
1.How long ------- you -------- here?
-Till next Friday.
A.are;staying B.do;stay C.here;stayed D.had;stayed
2.You will not go to the party,will you?
-No,--------- I've been invited.
A.if B.though C.unless D.because
(我选的是C，但答案是B）

1.How long ------- you -------- here?-Till next Friday.A.are;staying B.do;stay C.here;stayed D.had;stayed2.You will not go to the party,will you?-No,--------- I've been invited.A.if B.though C.unless D.because(我选的是C，但答案是B）
Howlong多久,后面得加延续性的动词,stay是短暂性的动词.你在这呆了多久应用be+doing形式表示延续性.
第二题是说你不去是吧?意思是你已经被邀请了,确认你不去.不能用unless.你回答是的,我不去,尽管已经被邀请了

进行时表将来 再如：
I am flying to Japan tomorrow
问题的意思是：你在这儿要呆多长时间?
直到下周五。

B

stay是延续性动词，可以表示一段时间的延续动作。till是直到，就是有时间延续的意思咯。next friday是将来时间。所以应该用延续的状态来提问。