She（thinks）（it's）easy for her.为什么think要加s 为什么要用i

She（thinks）（it's）easy for her.为什么think要加s 为什么要用i She thinks they are very exciting.这里的think为什么要加s吖? It's easy for me to play soccer.为什么play前面要加to? I Think　it’s too diffcult 为什么要加it’s it's not easy for people to learn english well.为什么要用to learn I think it's important (for us to learn)English well.为什么要填这个 I don't think it matters matters 为什么要加s It's easy for her to It's not easy to cross the rive on a ropeway为什么要加to It's easy to make such a mistake.make前为什么要加to she （think ）it is good 第三人称时 think用不用加s I think it's a good room for us to live in.为什么要填live in