start on something

• 着手做某事；开始

start on something的用法和样例：

例句

1. I would not know where to start doing it.
   我不知道从哪里着手做起。
2. We had many problems to surmount before we could start the project.
   我们得克服许多困难才能着手做这项工作。
3. She was lonely at the very start.
   她开始时感到孤独。
4. After a promising start, things began to turn sour.
   起先是很有希望的，后来却开始变得让人扫兴。