The words in parenthesis are that main words the questions wants you to answer.
Let's start with the first gap, the word in parenthesis is "climb", but we can't just put the word in the gap, we have to change it into its past tenses, so the word in the first gap would be "climbed".
In the second gap: the word in parenthesis is "see", but we can't just throw in the word to the gap, we have to also change it into its past tense, so the word in the second gap would be "saw".
This is the incorrect sentence: "Patrick climb the mountain and see a snake"
This is the correct sentence: "Patrick climbed the mountain and saw a snake"
