Tsunami waves can (break, build up) coral reefs. Tsunami waves also drag sediment from coastlines into the ocean, which can (smother, nourish) coral reefs and (magnify, block) sunlight that zooxanthellae need to photosynthesize.

Tsunami waves can break coral reefs. Tsunami waves also drag sediment from coastlines into the ocean, which can smother coral reefs and block sunlight that zooxanthellae need to photosynthesize.