i don't konw how to call it in English 等于

帮人帮到底。 ①she often helps her mother dothe huose work.=she often _ her mother_the huose work ②The boy was very clever ,he could make a model plane alone.=The boy was clever _to make a model plane _ _. ③she doesn't want to drink milk now.= she doesn't_ _ _milk now ④if you don't study harder,you won't catch up with the others=if you don't study harder,_ _ _the others 谢谢