Learning how to correctly pronounce "wonderful" in English is an important part of mastering the language. To pronounce the word correctly, start by saying the sound of "wuh" as in the word "wuh-nderful." Then, move on to the "uh" sound, as in the word "uh-nderful." Finally, complete the word with the sound of "ful," as in the word "wonder-ful."
When saying the word, make sure to emphasize the first syllable and be sure to keep the vowel sound in the middle of the word. It's also important to draw out the "ful" sound at the end of the word. To practice saying the word, try repeating it multiple times, emphasizing different syllables to get the feel of the word.
In addition, it's helpful to listen to native speakers say the word and to mimic their pronunciation. Once you've mastered the sound of the word, try saying it in a sentence to check your pronunciation.
With enough practice, you'll be able to confidently say "wonderful" in English.