For example, if I say the past tense verb “walked“, as in, “I walked away,” what is the last sound that you hear in the verb?
The “th” [θ] and [ð] sounds are commonly mispronounced by English language learners. This is not surprising, because in their first languages, the tongue simply does not move the way it does in English. To produce the “th” [θ] and [ð] sounds, we:
place the tip of the tongue between the teeth; then
blow air.
“th” [θ] (voiceless – no vibration in the vocal chords)
“th” [ð] (voiced – the vocal chords vibrate)
A failure to put the tongue between the teeth when making a “th” sound in English results in the:
voiceless [θ] –> [s] or [t]