Learn more about Grammar:
Adjectives: An Easy Guide with ExamplesAdverbial Clause: Definition, Meaning and ExamplesAdverbs: Definition, Meaning, Usage and ExamplesAnalogy: Definition & Meaning (with Examples)ArticlesBad Adverbs: What Makes an Adverb "Bad" and Why (with examples)Clauses: Definition, Meaning, and How to Use ThemConjunctions: Definition, Grammar Rules and ExamplesCoordinating Conjunctions: Definition, Meaning and ExamplesDangling ModifiersDeclarative Sentence: Definition, Meaning and ExamplesExaggerationHomophones: Definition and ExamplesInfinitivesInterjections: Definition, Meaning, and ExamplesIntransitive Verb: Definition, Meaning, and ExamplesNouns: Definition, Meaning and Types Explained (with examples)Participles PluralsPrepositional Phrase: What Is It & How to UsePrepositionsPronoun: Definition, Meaning and Types Explained (with examples)Split Infinitive: The Complete Guide (with Examples)Subordinate Clause: Definition, Types, and ExamplesSubordinating Conjunctions: What Are They? (with Examples in Sentences)The Complete Guide to Transitive VerbsTransition Words and Phrases in EnglishTypes of VerbsVerbs: Types of Verbs, Definition and ExamplesWhat Is Symbolism in Writing?Word ClassesWhen can I omit "that" from a sentence?

Omitting needless words is always a good practice, and that often falls into this category, especially when you use bridge verbs like say, think, know, claim, hear, or believe.
Consider the following:
- She believes that her husband is picking up the baby from daycare on his way home.
Clearly, we can cut that from this sentence.
Where it gets dicey is when you use non-bridge or transitory verbs. Omitting that can sometimes make your reader go back to the beginning of your sentence to try to understand your meaning.
The reader may have to go over this sentence again:
- Tanesha acknowledges being a member of a minority group may have made it harder for her to find gainful employment and appropriate housing.
This version is clearer:
- Tanesha acknowledges that being a member of a minority group may have made it harder for her to find gainful employment and appropriate housing.
A good rule of thumb is to rely on your inner ear. If the sentence sounds better and the meaning is clearer, by all means use that.