"I will run and you will walk."
Translation:jIqet 'ej bIyIt.
Klingon verbs don't mark tense, so it could be past, present or future. Most of the time, you can tell tense from context or time adverbs. But these beginning sentences are trying to keep it simple, so no context or adverbs. Thus, you can put any of the three tenses.
What you are missing is that there is no lowercase L in this exercise. Each of those letters is actually an uppercase i. Otherwise you would have three consonants in a row in the first word and 5 consonants in a row in the third word. Klingon does not have runs of consonants like that. Every consonant must have at least one vowel next to it (with an occasional rare and special exception for ' and gh only). If the Consonant-Vowel-Consonant pattern of Klingon syllables does not make it clear whether it is a lowercase L or uppercase i, you can also look carefully at the bottom of the letter. The lowercase L (l) has a small curl at the bottom that is missing from the uppercase i (I).