Sugar is uncountable; therefore, the sentence has a singular verb. Marbles are countable; therefore, the sentence has a plural verb. 3. Compound subjects joined by and are always plural. 4. With compound subjects joined by or/nor, the verb agrees with the subject nearer to it.
Panic disorder causes panic attacks spontaneous feelings of anxiety, terror, or impending doom. Physical symptoms include heart palpitations, chest pain, and shortness of breath. These attacks may be repeated at any time. People with any type of anxiety disorder may have panic attacks.
Other respiratory effects of anxiety may include pains or tightness in the chest, as well as a choking or smothering sensation. In more severe cases, blurred vision, dizziness, hot flushes, and confusion may also result from increased breathing. The Behavioral Effects of Anxiety.