hum and ha

== English == === Verb === hum and ha (third-person singular simple present hums and ha's, present participle humming and ha'ing, simple past and past participle hummed and ha'd or hummed and ha'ed) (UK) Alternative form of hum and haw. ==== Usage notes ==== The inflections of ha can be rather tricky. Three different present-participle forms are used: haing, ha'ing and ha-ing. Has may be avoided because of confusion, in writing, with the verb have.