You don't know whether the shoes fit you ________ you try them on.
A.if B.unless C.though D.when
To make your DIY work perfect, you'd better not start ________ you get all the tools ready.
A.when B.since C.before D.after
It has been five years________ I last saw my primary school classmate Lucy.
A.though B.until C.since D.before
________ the river is polluted, it will take years to become safe and clear again.
A.Once B.Although C.Until D.Unless
A true friend can see the pain in your eyes ________ everyone else believes the smile on your face.
A.while B.until C.before D.because
(2016●南通市)Jack is still working to high standards he has made great achievements.
A.until B.if C.though D.because
