There are two things you can do to make the use of a mantra more powerful, regardless of how you recite. One is to see the mantra, as if it is being written as you say it, and the other is to actively listen to it as you say it, perhaps, in this case, when using the first two languages.
ONG NA MO GURU DEV NA MO
Salutations to the Guru within.
Means "Truth is my identity." SAT is a Bij Mantra or a "seed sound." Chanting Sat Nam is like planting a grain of sand in an oyster. Our truth gathers around the grain. Over time, as we accumulate our gifts and gather our true essence into our consciousness, we become the pearl of Self.
EK ONG KAR, SAT NAM SIRI WHA (HE) GURU
This is the Adi Shakti Mantra, and it is very powerful for awakening Kundalini and suspending the mind in bliss. Ek means "One, the essence of all", Ong is the primal vibration from which all creativity flows, Kar is "creation", Sat "truth", Nam "name" Siri "great", Wha "ecstasy," and Guru is "wisdom". Taken together it means, "There is one Creator whose name is Truth. Great is the ecstasy of that Supreme Wisdom."
GURU GURU WAHE GURU, GURU RAM DAS GURU
This mantra calls upon Guru Ram Das in praise of his spiritual guiding light and protective grace.
ONG SO HUNG
This mantra proclaims "Creator, I am Thou!", a heart-opening and empowering mantra.
SA TA NA MA
This is the Panj Shabad expressing the five primal sounds of the universe. "SA" is Infinity, "TA" is life, "NA" means death and "MA" is rebirth. (The 5th sound is "A".) This is one of the most frequently used mantras in Kundalini Yoga.
This is the Guru Mantra, the mantra of ecstasy. It is not translatable but chanting it elevates the spirit.
AD GURAY NAMEH, JUGAD GURAY NAMEH,SAT GURAY NAMEH, SIRI GURU DEVAY NAMEH
This mantra is the Mangala Charn Mantra, and is chanted for protection. It surrounds the magnetic field with protective light, and means "I bow to the primal Guru (guiding consciousness who takes us to God-Realization), I bow to wisdom through the ages, I bow to True Wisdom, I bow to the great, unseen wisdom."