Yes, it is.

It is not that you can not speak English,but that you do not speak Enlish while you can.

You have leared many words and you'd better try your best to use them this way and that way so that you can master English.

没错。不定词当定语，统计上相对罕见。但，分析是对的。

下例中，to do 亦是相同用法：

The students still have a lot of homework [to do].