Questions & Answers about Im Semester haben wir oft viel Stress.
Why does the sentence start with "Im" instead of just "In"?
Im is a short form of in dem. When you talk about a time period to answer the question "when?", German uses the dative case. Since Semester is a neuter noun (das Semester), it changes to dem Semester in the dative case, and in dem shrinks to im.
Why is the verb "haben" placed before the subject "wir"?
In a normal German sentence, the main verb must sit in the second position. Because the time phrase Im Semester takes up the entire first position, the verb haben has to come next. This pushes the subject wir into the third position.
Why do we use "viel" here instead of "viele"?
You use viel (much / a lot of) for uncountable nouns, which are things you cannot count individually, like water, time, or Stress. You only use viele (many) for countable things, like viele Studenten (many students).
Could I say "wir sind stressig" to mean we are stressed?
No, that is a common trap! In German, you usually say you have stress (Stress haben) or that you are stressed (gestresst sein). If you say Wir sind stressig, it actually means that you are stressful people who cause stress for everyone else!