He is a man who. A common type of redundant expression; see [Rule 13].

He is a man who is very ambitious.He is very ambitious.
Spain is a country which I have always wanted to visit.I have always wanted to visit Spain.

Help. See under [But].

However. In the meaning nevertheless, not to come first in its sentence or clause.

The roads were almost impassable. However, we at last succeeded in reaching camp.The roads were almost impassable. At last, however, we succeeded in reaching camp.

When however comes first, it means in whatever way or to whatever extent.

However you advise him, he will probably do as he thinks best.

However discouraging the prospect, he never lost heart.

Interesting. Avoid this word as a perfunctory means of introduction. Instead of announcing that what you are about to tell is interesting, make it so.

An interesting story is told of(Tell the story without preamble.)
In connection with the anticipated visit of Mr. B. to America, it is interesting to recall that heMr. B., who it is expected will soon visit America