Answer:
1. Astronaut (look)= The astronaut <em>looked</em> at the sky.
2. Scientists (research)= The scientists <em>researched </em>the possibility of discovering a vaccine for the Ebola virus.
3. Boredom (stimulate)= His boredom <em>stimulated</em> his desire to get angry at anyone.
4. International Space Station (will be)= The International Space Station <em>will be</em> the station where astronauts are stationed in space.
Explanation:
Using the correct form of the verb will be to use the verb in accordance with the sentence structure. So, if the sentence is talking about past events, then the verb will be in the past tense, and so on.
Framing sentences using the subject and the verb in parenthesis are as follows-
1. Astronaut (look)= The astronaut looked at the sky.
2. Scientists (research)= The scientists researched the possibility of discovering a vaccine for the Ebola virus.
3. Boredom (stimulate)= His boredom stimulated his desire to get angry at anyone.
4. International Space Station (will be)= The International Space Station will be the station where astronauts are stationed in space.
