129. By end of the writing workshop, participants will have gained a thorough ___ of the rules of grammar


(A)understand(B)understanding(C)understandably(D)understands


답(A)





130. Driver waiting in the loading zone must switch off the engines of their delivery vans and avoid leading them


(A)idle (B)valid (C)blank (D)empty


129번은 답이 왜A인가요??


130번은 저 자리에 왜 형용사가 들어가지요??