undoubtedly
A synonym for changable is adaptable.
A synonym for common noun is word.
A synonym for debris is garbage. An antonym for debris is cleanliness.
A synonym for the word "sensor" is "detector".
attitude of doubt is skepticism
suspicion
The synonym for suspect is "doubt" or "distrust."
without doubt; certainly
A synonym for "scruples" is "qualms," which refers to feelings of doubt or unease about a course of action, especially when it involves ethical considerations.
Skepticism, doubt, wariness, misgiving, suspicion...
without any doubt... the answer is to sustain or prevail.
vagueness, doubt, uncertainty, obscurity, equivocation, dubiousness
doubt
A synonym that has a meaning similar to the word believes is the word trust. An antonym to the word believes that has an opposite meaning of it is the word doubt.
Some synonyms for uncertainty are doubt or distrust.
protraction, uncertainty, doubt, solicitude, cessation, pause, waiting, intermission, discontinuance, abeyance, stoppage, indetermination, indecision
pain, hurt, ache, throbbing, irritation, tenderness, pang, malaise, uneasiness, worry, anxiety, doubt, distress, trepidation