21. —You can’t enter the building without _______ permission.
—I’ve lost _______ permission card.
A. the,a B. a,the
C. 不填,the D. 不填,不填,
22. _______ _he works hard,I don’t mind when he will finish the experiment.
A. As soon as B. As well as
C. So far as D. So long as
23. —No more problems so far?
— _______ .All seems to be in order.
A. Yes,I think so B. No,I don’t think so
C. Yes,I don’t think so D. No,I think so