What's the conditional?
Chuck isn't stupid, but he fails his midterm exams. Why? -- He never studies for it.
"If Chuck studied, he probably wouldn't fail his midterm exams."
Wood ______ (not burn) if there is no air.
doesn't burn
Make a first conditional sentence. ( You / to forget my birthday / I / to speak never to you again)
"If you forget my birthday, I'll never speak to you again".