用所给动词的适当形式填空。 1. This road (break) down by the flood all the time. 2. We _ (teach) how to do experiment in the lab yesterday, 3. A supermarket (build) near our building next year. 4. These flowers___ _ (should water). look! The soil under them is almost dry. 5. These used books____ (can reuse) by those new students. 6. Those dangerous houses _ (may damage) once again by the aftershock(余震).