bulk up
phrasal verbbulk something out/up
to make something bigger, thicker or heavier 使加大（或加厚、加重） Sausages often have bread in them to bulk them out. 香肠里通常有面包来使它们变大。 He acquired another small airline and bulked up operations. 他收购了另一家小航空公司，扩大了业务。