Click on the first letter of any word in the grid (these are numbered).

The clue appears top left of the screen. If the square is the first letter of two words - vertical and horizontal - the two clues will appear.

Type your answer in the white field and click on "Enter". If your guess is correct, the word will appear in the crossword.. If you cannot guess, click on "Hint" and the next letter will be seen.

Click on "Check" (at the bottom) to see if your completed crossword is correct: Any wrong letters will be removed.

The activity looks like this. In this screen the clue is a picture: