DE (means: down, away, remove)
Re (Again)
Sub (Under)
Spec (Look)
Pre (Before)
100

To take something off or erase it.

Delete

100

To read something again

Reread

100

A sandwich is sometimes called this.

Sub

100

Glasses you wear to see.

Spectacles

100

A test before learning.

Pretest

200

To go down from somewhere.

Depart

200

To play a game again.

Replay

200

A boat that goes under water.

Submarine 

200

To look carefully at something.

Inspect

200

To get ready before something happens.

Prepare

300

To move away from a place.

Depart

300

To build again.

Rebuild

300

Something written under a picture or video

Subtitle

300

People watching a game.

Spectators

300

To tell what will happen before it does.

Predict

400

When something gets smaller or less.

Decrease

400

To turn back to something.

Return

400

To take the place of another person. (Think soccer, sports, school)

Substitute

400

To look over something to check it.

Inspection

400

To stop something before it happens.

Prevent

500

To make something weaker or less strong.

Degrade

500

To think again about something.

Reconsider

500

Something below the surface.

Submerge

500

Something special to look at.

Spectacle

500

A show before the main show.

Preview