Thank you for usso much help.—You are welcome.

填入下列文段空白处的词语，，最恰当的一组是（ ）近年来，我国环境保护工作形势严峻，环境污染问题越来越严重，其中 ① 有多方面的原因， ② 根本原因在于部分企业和个人法律意识淡薄，有些政府官员环保责任意识不强。③ 要尽快扭转这种局面， ④ 通过切实施行相关法律规定，进一步完善环保责任制， ⑤ 能实现。 ①②③④⑤

One advantage of playing the guitar is _____ it can give you a great deal of pleasure.

We met an old friend in London _________ our expectation. Shewaved at us ________ the street when she saw us.

The sports meeting will be held on the playground this weekend, ifweather______.[ ]