This drug contains no _____ substances and has no side effects.
举一反三
- Every drug has some side effects.
- The drug has several side ( ). A: affects B: infects C: effects D: defects
- The side effects of the new drug are being __________ researched.
- The side effects of the new drug are being __________ researched.(extensively)
- If it is taken in small doses, the drug has no harmful effects.