Bas

ex(basement, basic, base)

Low

Cap, Capt

ex( Capture, capable, captivated, capsize)

Cred

ex(credible, credence, credentials, credenza)

Dict

ex(predict, dictionary, dictator, dictation)

Duc, Duct

ex(reduce, conduct, reductivenesses

Fac, Fact

ex(factor, facetious, factotum)

Graph

ex(hydrographical, autograph, graphics processing unit)

Log

ex(Schoology, microbiology)

Mort

ex(immortal, mortal, mortality)

Scrib, script 

ex(scriptures, subscribe)

Spec, Spect

ex(suspected, Speculation)

Tact

ex(phototactic, phonotactic)

Ten

ex( hyperextended, intentionally)

Therm

ex(thermos, hypothermia,)

Ver

ex(verification, solve)