I'd forgotten because some other thought was trying to push its way up.

His thoughts tried to wander leagues away, but they kept coming back to the present moment, location, and companion.

A thought was trying to burrow up out of my befuddled brain.

At least, that's what the humans and the alien thought they were trying to do.

Every now and then, a thought tried to break through the darkness that blanketed her.

The thought had come unbidden; but try as she might, she couldn't drive it away.

Another thought tried to make itself heard: No-no-it shoots high.

The youngest thought to try as well, because he was not rich enough to support all three of them.

Just a thought - from a guy, so take this with a grain of salt: don't try too hard to dress conservative.

She pushed the unpleasant thought away, tried to focus on something else.