He started to learn English in 1990 and in the years ________ he kept on using it in his work.
I’ll prepare more dishes_________ your guests decide to stay for dinner.
Large quantities of information, as well as some timely help _____ since the organization was built .
---Mary’s score on the test is the highest in her class. ---Really? She ______ have studied very hard.
George, the lonely tortoise, was said ________ on a tiny island of Pinta in 1971.
______ left before the deadline, it doesn’t seem likely that John will finish the job.