a. to dress b. dressed c. dressing d. having dressed
2. to satisfy the visitors, the zoo will ______ business hours until 6:00 p.m. during the may day holiday.
a. expand b. enlarge c. widen d. extend
3. if you want to know what this material ______, you must observe it under a microscope.
a. involves in b. makes up c. consists of d. adds to
4. when ______ for his views about hi