Select all that apply: which sentences use an allowed first-conditional main-clause form?
If the workshop finishes early, you may catch the 17:20 train.✓Correct answer
If the path splits near the lake, follow the blue markers.✓Correct answer
If the workshop will finish early, you may catch the 17:20 train.
If the path splits near the lake, you will must follow the blue markers.
Explanation
The workshop sentence correctly uses a modal, and the navigation sentence correctly gives an imperative. The other sentences put will in the condition or combine two modal verbs incorrectly.