不可以。say hi的字面意思是“說一聲嗨（你好）”，一般用在say hi to sb.中，意思是“和某人打招呼”。例句：Okay, so say hi to my friend and tell him that you like the hat.

Would you like to come up and say hi to everyone for me?

來向大家打個招呼好嗎？

Do you want us to come say hi to her parents?

要我們下去跟對方父母打個招呼嗎？

-Say Hi to people and make friends with your colleagues.

-和你的同事打招呼，交朋友。

I thought I'd come by and say hi.

我想我應該過來跟你們問好。

I mean, you don't even say hi to me.

我是說，你還沒向我打招呼。

來源：高三網(wǎng)