He can go with you—always assuming he can spare the time.
句中的always assuming是什么意思？什么用法？

查《朗文當代英語詞典》always詞條，有always assuming / supposing (that) sth?這一固定搭配，其解釋是：BrE used to say that one important fact has to be accepted as true for something else to happen, be true etc.（要是……的話）。

《朗文當代英語詞典》的相關例句是：

We’ll leave on Tuesday—always assuming the car’s repaired by then.?我們禮拜二出發(fā)——如果那時車子能夠修好的話。