So why didn’t you say “hello” to him yesterday? —Well, I stopped and smiled when I saw him, but he_____ me and walked on. [ ]

The Education Department says that school safety has set off alarm bells with frequent reports of serious accidents ________ students got injured or killed.[ ]

The experts present at the conference all insisted that greenhouse gas emissionbe reduced from now on．

According to the regulations, anyone who has the intention to be a teacher _______ pass a series of demanding tests.

Do you know Tom very well— Yes, he and I _______ friends since we met in yangshan the year before.