Complete the exercise shown.

Here are the answers for the given exercises: 1. For the image labels: - 1: mountain - 2: river - 3: lake - 4: island - 5: sea 2. For the crossword puzzle: - Across: - 1 (We can go up this. It's very high.): mountain - Down: - 2 (We can cross this on a bridge.): river - 3 (We can swim here.): lake - 4 (There's water all round this.): island The hidden word is: mountain.