Tom prefers to telephone his parents rather than write to themTom prefers __ his parents ___ writing to them .

问题描述:

Tom prefers to telephone his parents rather than write to them
Tom prefers __ his parents ___ writing to them .

前一个空可填calling,后一个填to,因为to是介词,所以to后面接动名词,prefer后面必须与to保持一致,所以也填动名词.