A team that works together as one group is...
"Uni" or "mono" both mean "one". An antonym for these words could be...
vowel sound
color
mono
Something that is all one color is called...
one
Single sound words like "me", "you" or "it" would be called...
chrome
syllable
Riding a _____ is difficult, because it only has one wheel.
united
unicycle
monochrome
Many
speaking in one tone of voice
"Uni" or "mono" both mean "one". Possible synonyms could be...
'single'
monosyllable
Single or solo.
uni
monotone